Question

what is relative clause and relative pronouns ​

Answer 1

A relative pronoun is used to connect a clause or phrase to a noun or pronoun. The clause modifies, or describes, the noun. The most common relative pronouns are who, whom, whose, which, and that. Sometimes when and where can be used as relative pronouns as well.

Answer 2

the clause qualifies a noun is called relative clause
eg the boy,who is sitting on the floor , is my best friend

the relative pronoun stands instead of a noun and also join sentences .

eg who,which ,whom,that,whose etc
hope this will help you